! have just finished constructing my first Prusa Mendel Iteration 2.
All the motors X axis/Y axis/Extruder work fine in both directions.
Z motors are OK when lowering the X carriage but struggle to raise it.
My NEMA 17 stepper motors are advertised as 48Ncm which is above the minimum 40Ncm mentioned in various Wikis.
When the Z screwed rods are disconnected from their coupling, the motors rotate freely in both directions.
Logic tells me that it is a mechanical problem, being harder to lift something than lower it.
I checked that the Z smooth rods are parallel and that the X carriage is not skewed horizontally.
Any ideas of where the problem lay would be most welcome.
All the motors X axis/Y axis/Extruder work fine in both directions.
Z motors are OK when lowering the X carriage but struggle to raise it.
My NEMA 17 stepper motors are advertised as 48Ncm which is above the minimum 40Ncm mentioned in various Wikis.
When the Z screwed rods are disconnected from their coupling, the motors rotate freely in both directions.
Logic tells me that it is a mechanical problem, being harder to lift something than lower it.
I checked that the Z smooth rods are parallel and that the X carriage is not skewed horizontally.
Any ideas of where the problem lay would be most welcome.
